Wireless communication systems may be used, such as German Patent Application No. 44 44 727, for example, which proposes connecting various control units, which are interconnected via a data bus, in a motor-vehicle, via a wireless interface to an external read unit. In this context, an interface module provides the connection to the wireless interface. This module is assigned to a selected control unit. As examples of data transmissions, those in the infrared or high-frequency range are mentioned. No reference is made of a specific implementation of this interface, particularly with regard to the requirements for a high transmission rate, interference resistance, and/or transmitting capacity for a data transmission from the engine compartment, etc.